Background: Intensified therapies convey a survival advantage over androgen deprivation therapy (ADT) alone in metastatic hormone sensitive prostate cancer (mHSPC). We sought to identify area- and patient-level factors that are associated with intensification of therapy among mHSPC patients treated in US health systems. Methods: Electronic health records from OPTUM were used to identify patients aged ≥18 with mHSPC who received ADT between 2020 and 2022. Treatment intensification was defined as receiving one of the following within 90 days of initiation of ADT: apalutamide, enzalutamide, abiraterone +/- prednisone +/- docetaxel, darolutamide +/- docetaxel, docetaxel +/- other systemic therapy, and external beam radiation therapy (EBRT). Multivariable logistic regression was used to determine factors associated with intensification. We used Chi-squared tests to select the model with the best statistical fit. Results: We identified 1,123 patients with mHSPC who received ≥1 ADT in the post-index period with mean age of 71.2 (9.5), 73% Caucasian, 18% African American, and 2% Asian. Overall, 640 (57%) patients received treatment intensification within 90 days of ADT initiation. The proportion of patients receiving intensification increased from 53% to 63% between 2020 and 2022. The most common intensification treatments were abiraterone acetate (46%) and enzalutamide (38%). The median time to first treatment after metastasis was 15 days for receiving intensified therapy and 34 days for non-intensified therapy. In multivariable logistic regression, younger age, presence of bone/bone marrow metastasis at baseline, region (Northeast and West), and lower modified Charlson Comorbidity Index (CCI) score (excluding cancer) were significantly associated with receiving intensified therapy (Table). PSA was not included in models due to substantial missingness (40%). Conclusions: Just over half of eligible patients received treatment intensification following ADT. There are also significant disparities in treatment by age, region, and site of metastases. Future studies examining physician and patient preferences for intensification, as well as possible misperceptions and biases, would provide evidence to address undertreatment in this setting.

Note: Age and modified CCI score were not included within the same model due to multicollinearity.